Why has Bootstrap changed styles on other sites?

Question

css

I started using Bootstrap 4 in one project, connected it on an HTML page via CDN.
Everything is in a beam, it works, the project is finished.
But now on third-party sites I noticed that the style of various forms and buttons has changed.
How to return back? How does it work like that?)

The browser, of course, is Chrome. Cleaned cache.
OS Linux Manjaro.

Answer 1

If you're talking about black strokes on focus, then these are the new chrome styles. Change outline on focus